The calorie number in an app or on a package is not a verdict or a daily task. It is a guideline that helps you see roughly how much energy you get and spend. Let's break down where the reference norms come from and why they differ between two people.
What is the daily calorie norm
Energy from food and drinks is measured in calories, and the body needs it to function: breathe, move, grow, think. If calories coming in equal what the body expends, weight stays roughly stable. If we eat and drink more than we spend, the excess energy is stored as fat; if less, the body draws energy from reserves.
Labels usually show kcal — kilocalories, and next to it may be kJ — kilojoules. In dietetics, the prefix "kilo" is often dropped and people just say "calories," though they mean kilocalories; one kilocalorie is 1000 calories. A calorie itself is a unit of heat: the amount of energy needed to raise 1 gram of water by 1 degree Celsius.
How many calories women need
The reference guideline for an average woman is about 2000 kcal per day. This is an averaged figure for a person with certain weight, height, age, and activity level, not a personal prescription.
How many calories men need
The guideline for an average man is about 2500 kcal per day. For a specific person, the value may differ depending on age, weight, height, and physical activity.
Calorie norm for adolescents
The reference materials used do not provide a separate figure for adolescents. General factors that can affect energy needs are age, weight, height, and physical activity. A doctor can suggest a specific number.
What determines individual energy needs
Energy needs can be influenced by:
- age, weight, and height;
- physical activity: the more movement, the more energy is spent — brisk walking burns more than leisurely walking;
- health status and medications that can affect weight, such as steroids and some antidepressants; among conditions — Cushing's syndrome and polycystic ovary syndrome.
What the calorie guidelines mean and their limitations
The numbers 2000 and 2500 kcal are averages. Personal needs may differ from these values due to age, weight, height, and physical activity. To assess weight relative to height, body mass index is used — a measurement that shows whether your weight is healthy for your height.
On a food package, energy value is usually given in kilocalories and kilojoules under the heading "energy." This is reference information about the amount of energy in the product. One kilocalorie corresponds to about 4.2 kilojoules. A kilojoule is a unit of energy.
A doctor can help determine the weight that is right for you and your goals.
The topic of calories and weight alone is not a reason to call an ambulance. Numbers 103 and 112 — if there is a threat to life: signs of stroke or heart attack, severe injury, for example after a serious road traffic accident.
This material is for reference and does not replace a doctor's consultation: only a specialist will assess your situation as a whole.
Sources
Update history
Reader reviews
No reviews yet — tell us whether this article was helpful.
Leave a review
This content is for reference and does not replace a doctor's consultation. Medical disclaimer